Simulations of how stars’ lives affect galaxies

The Universe contains a multitude of galaxies, everything from small dwarf galaxies to enormous elliptical ones. To understand how this diversity arose, Oscar Agertz will investigate how massive stars influence the dynamics of a galaxy, conducting these experiments using simulations in supercomputers.

When researchers simulate the development of the universe in supercomputers, they often only succeed in predicting the growth of extremely massive galaxies. The formation of thin spiral galaxies, such as our own Milky Way, are difficult to predict using present models.

A major problem is the lack of knowledge about the ways in which massive stars influence how galaxies develop. For example, how does the enormous amount of energy released from dying stars lead to material being thrown out from galaxies?

To gain a better understanding of the interplay between stars and galaxies, Dr. Oscar Agertz from the University of Surrey, United Kingdom, will conduct supercomputer simulations in which massive stars are born and die, while he follows the development of a galaxy. No researcher has previously carried out simulations that include objects of such vastly different sizes, but this is necessary to obtain a detailed model of how galaxies form and evolve in our universe. As a Wallenberg Academy Fellow, Oscar Agertz will move his activities to Stockholm University.

“It is a great honour to become a Wallenberg Academy Fellow. It makes it possible for me to form a research group that can really focus on my research programme”, Oscar Agertz says.